gh-92886: make test_ast pass with -O (assertions off) (GH-98058)

-O does not strip docstrings.

Automerge-Triggered-By: GH:iritkatriel
(cherry picked from commit 27ce45d)

Co-authored-by: Irit Katriel <1055913+iritkatriel@users.noreply.github.com>

Lib/test/test_dis.py

@@ -1076,7 +1076,7 @@ def get_disassembly(self, func, lasti=-1, wrapper=True, **kwargs):
         return output.getvalue()
 
 
-if sys.flags.optimize:
+if dis.code_info.__doc__ is None:
     code_info_consts = "0: None"
 else:
     code_info_consts = "0: 'Formatted details of methods, functions, or code.'"